Amplified Pressure Transducers Using SOI Sensors and SOI Electronics, Suitable for High Temperature Operation (250°C)

In an effort to improve efficiency, reliability and reduce costs, engineers are moving towards distributed control systems on trains, cars, planes and other systems in place of centralized control systems. In a distributed control system, sensors, processors and actuators are all located together at remote locations [1]. Distributed control systems require significantly less cabling which leads to weight reductions and therefore cost and energy savings. To implement distributed control, in many applications sensors and their electronics must be able to withstand higher temperatures. Kulite Semiconductor Products has therefore developed a high temperature amplifier to be coupled with high temperature pressure sensors. While the suitable sensing technologies have been under the development for some time, the development of an Application Specific Integrated circuit (ASIC) utilizing SOI technology is now introduced and optimized. This paper reports on the latest developments of the Silicon-On-Insulator (SOI) piezoresistive sensors, the SOI application specific integrated circuits (ASICs) and the high temperature packaging of the two together. The design of the latest miniature amplified-pressure transducers capable of operating reliably under extreme environmental conditions (in excess of 250°C and under accelerations of greater than 200g) is described in detail. The performance of such amplified pressure transducers is presented and indicates that ruggedized, piezoresistive transducers with excellent static and dynamic performance characteristics are capable of operation in extremely harsh, high temperature environments.